1. Field of the Invention
This invention relates to electromagnetic stainless steels usable for use in iron core for electromagnetic valve, iron core for relay, magnetic shield, yoke and the like, and more particularly to an electromagnetic stainless steel having improved magnetic properties and electric resistance in ferritic electromagnetic stainless steel and excellent cold forgeability and machinability.
2. Description of the Related Art
From the old time, chromium-iron stainless steels are known as a corrosion-resistant material. And also, 13Cr steel, 18Cr steel and the like are mainly and widely used as a ferritic stainless steel in a field of magnetic materials requiring the corrosion resistance.
Concretely, the corrosion-resistant soft magnetic materials comprised of the above electromagnetic stainless steel are frequently used as an iron core of electromagnetic valve, iron core of relay and other electromagnetic materials used under corrosion environment, or as a magnetic shield material incorporated in an electric part such as a shield plate for casette tape recorder, shield material for power transformer and the like.
In the conventional electromagnetic stainless steel, it is desirable that the cold forgeability and machinability are improved while maintaining the corrosion resistance from a viewpoint that the electromagnetic stainless steel as a raw material is finished into a given shape by cold plastic working and cutting.
Furthermore, it is particularly desirable to improve the magnetic properties and electric resistance in the applications of the electromagnetic stainless steel in addition to the improvement of cold forgeability and machinability.
In this type of the electromagnetic stainless steel, therefore, it is demanded to improve not only the cold forgeability and machinability but also the magnetic properties and electric resistance.